The proposed research involves a 7-10 year follow-up of identified populations of young adults to determine factors in adolescence associated with subsequent hypertension. We propose to follow young mothers who, as adolescents, experienced hypertension during their first pregnancy and similar young mothers, normotensive during pregnancy. Recent follow-up studies at 3-6 years post partum indicate that women hypertensive during pregnance and their children have higher blood pressures than controls; 14% of women hypertensive during pregnancy, but no control women, were found to have blood pressure greater than or equal to 140/90 on repeated measurements, and EKG studies showed evidence of increased left ventricular wall thickness. Group differences in renin-aldosterone responses to exercise were also found. We propose to follow these women and their children to determine whether hypertension of pregnancy is associated with subsequent hypertension and the emergence of hypertensive cardiovascular disease in young mothers, and higher blood pressures in their children compared to controls. We also propose a follow-up of young adults who participated in a blood pressure screening project during high school in 1973. A five year follow-up in progress indicates that individuals in this population maintain their relative rank-order for blood pressure over time, and blood pressure measurements during adolescence are predictive of subsequent blood pressure. Relatively high blood pressures are associated with an increased prevalence of abnormal echocardiograms and exercise EKG studies. We propose to re-evaluate these individuals after 7-10 years to determine if relative blood pressure rank is maintained; to determine whether relatively high blood pressure in adolescence predisposes to hypersion and hypertension of pregnancy; to study aggregation of cardiovascular disease risk factors in young adults; to identify early evidence of cardiovascular disease. Sympathetic nervous system activity, the renin-aldosterone axis, and steroid responses to graded ACTH infusions will be studied in "pre-hypertensive" young adults to identify mechanisms that may be involved in the pathogenesis of hypertension. We will also study the effects of an exercise intervention program on high blood pressure in young adults.